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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Cue-Controlled Relaxation: Saving Time Versus Efficacy

Todd, John Bruce 08 1900 (has links)
Cue-controlled relaxation is looked at to determine whether a component is efficacious as the entire procedure. Subjects were 40 male and 40 female undergraduates. Subjects were randomly assigned to one of four conditions: cue-controlled relaxation, progressive muscle relaxation, breathing exercises with a paired. cue word, on a presentation of the cue word without being paired. It was hypothesized that cue-controlled relaxation would be superior to a component of cue-controlled relaxation. It was determined that cue-controlled relaxation is not more efficacious than a particular component. Data suggests the majority of anxiety reduction takes place when the treatment focuses on the same modality from which the subject receives the most information about their anxiety. Implications and suggestions for further research are presented.
162

Control of Heart Rate by Progressive Relaxation Techniques and Cerebral Electrotherapy

Chambers, Jim A. 12 1900 (has links)
This study presents the findings of an investigation of the effects of two different treatments, progressive relaxation and cerebral electrotherapy, on heart rate. With progressive relaxation, the subject relaxes by following instructions. With cerebral electrotherapy, relaxation is due to an external source of stimulation. Decreases in heart rate for subjects receiving progressive relaxation were compared with decreases for subjects receiving cerebral electrotherapy. A placebo group was used to evaluate the effects of both treatments independently. While decreases in heart rate were observed for both treatments, only progressive relaxation produced decreases significantly greater than those of the placebo group. However, decreases in heart rate produced by progressive relaxation were not significantly greater than decreases produced by cerebral electrotherapy.
163

Characterization of mechanical properties for polyethylene gas pipe materials

Popelar, Carl Frank January 1989 (has links)
No description available.
164

RELAXAMENTO PSICOFÍSICO EM CRIANÇAS

Fernandes, Elaine Ferrão 08 March 2005 (has links)
Made available in DSpace on 2016-08-03T16:34:28Z (GMT). No. of bitstreams: 1 ELAINE F FERNANDES.pdf: 724683 bytes, checksum: e96a0d1306ccd662e5059be967ebf83d (MD5) Previous issue date: 2005-03-08 / Research of bibliographical and monographical nature, this paper investigates the psychophysics relaxation in the health area, of children in a period of eight years, between January 1997 and November 2004. Initially, based in neuropsychological literature, it describes the relaxation role in homeostasis and the conscious body health, emphasizing the pleasure and painful behavior. Next, it describes and analyses several relaxation techniques, Jacobson Progressive Relaxation, Schulz Autogenos and Michaux Relaxation. To develop this research it was used 27 databases, due to the lack of production of this theme, per base. As result, it shows the total of 500 articles about relaxation, 200 of them related to children. They are national and international articles, most of them in English. Following this, it classifies these group in production by year, showing a significant increasing, although it is not systematic in number, from 14 articles in 1997 to 39 in 2004. As for the thematic, the data reveals first, the interest in pain, second in breathing problems and third in anxiety. The articles about pain, as they are in more quantity, have more detailed analysis, with discrimination by year, situation type, relaxation usage and pathology characterized by painful behavior. Finally, it is made a classification of the articles due to the usage of relaxation in clinical problems mainly the physical ones, those of affectionate-emotional psychic background, those with no usage of drugs and those with psychic background with the aid of drugs and psychiatric treatment. To discuss the results, several articles researched are also mentioned. Due to the richness of data, showing up the increasing of professionals in this health area, it is suggested further reading / Trabalho de natureza monográfica bibliográfica investiga o relaxamento psicofísico na área da saúde, em crianças, por um intervalo de oito anos, entre janeiro de 1997 e novembro de 2004. Inicialmente, com base em literatura neuropsicológica, descreve o papel do relaxamento na busca da homeostase e da consciência corporal saudável, enfocando comportamentos de prazer e dor. A seguir, descreve e analisa diversas técnicas de relaxamento, Relaxamento Progressivo de Jacobson, Autógeno de Schultz e Relaxamento de Michaux. A fim de desenvolver sua pesquisa utiliza-se de 27 bases de dados, devido a pouca produção encontrada sobre o tema, por base. Como resultados, levanta ao todo 500 artigos sobre relaxamento, sendo 200 em crianças. São artigos nacionais e internacionais, com predomínio do idioma inglês. A seguir, classifica esses artigos por ano de produção, constatando um crescimento significativo, porém não sistemático em seu número, de 14 artigos em 1997, para 39, em 2004. Quanto à temática, os dados revelam em primeiro lugar, um interesse em dor, em segundo em problemas respiratórios, e, em terceiro lugar, em ansiedade. Os artigos sobre dor, por serem os mais numerosos levantados, sofrem análise mais detalhada, com discriminação da quantidade de artigos por ano e dos tipos de situação e de patologia caracterizados por quadro álgico. Finalmente é feita uma classificação dos artigos segundo a utilização do relaxamento junto à problemática clínica predominantemente física, a de fundo psíquico afetivo-emocional, sem utilização de fármacos e, a de fundo psíquico, com intervenção psiquiátrica farmacológica. Na discussão dos resultados, vários artigos pesquisados são também comentados. Dada a riqueza dos dados, evidenciando interesse crescente de profissionais da área da Saúde na literatura levantada, sugere-se pesquisa complementar
165

Probing Dynamics of Oligosaccharides by Interference Phenomena in NMR Relaxation

Ghalebani, Leila January 2008 (has links)
<p>Oligosaccharides (carbohydrates) are a large class of biological molecules that are important as energy sources in the human body and have enormously varied biological functions. It is generally believed that biological activities of carbohydrates are related to their internal dynamics. The dynamic properties of some oligosaccharides in solution are studied in this thesis, by NMR relaxation. We have employed relaxation interference effects to investigate the conformational dynamics within oligosaccharides (in-tramolecular dynamics) and paramagnetic relaxation enhancement (PRE) as an experimental tool to study intermolecular dynamics. Most of the thesis concerns the dynamics of the methylene group in the two possibly mobile parts of the oligosaccharide: in the exocyclic hydroxymethyl moiety and in the glycosidic linkage position. To perform conformational dynamic studies, the more traditional auto-relaxation pa-rameters are combined with the relaxation interference terms or the cross-correlated relaxation rates (CCRRs). Some experimental schemes based on the initial-rate technique were developed for measuring CCRRs. The techniques are useful for labelled sugars as well as naturally abundant ones. Furthermore, various dynamical models ranging from the Lipari–Szabo approach to several more informative and complicated models such as the two-site jump model, restricted internal rotation and slowly relaxing local structure (SRLS), have been employed to interpret our experimental data. We have combined and com-pared different models; we have also developed a novel approach to existing models, by scaling dipolar coupling constants (DCC), to extract the dynamic behaviour and structural properties of the system. We found that the auto- and cross-correlated relaxation data analyses yield a consistent picture of the dynam-ics in all cases. Additionally, our investigations show that CCRRs are practically important for verifica-tion of certain dynamical and structural information that is difficult to be determined by other means. Moreover, the anisotropy of the carbon-13 chemical shielding tensor in the methylene group has been estimated, using the interference between dipole-dipole and chemical shift anisotropy.</p><p>This thesis also discusses using the PRE to investigate sugar dynamics relative to a paramagnetic MRI contrast agent in solution, which might be important in medicine. We have studied the intramolecu-lar dynamics of the trisaccharide raffinose in the presence of a gadolinium complex. We also investigated the effect of translational diffusion instead of rotational diffusion, which is normally more important in NMR. The paramagnetically enhanced spin–lattice relaxation rates of aqueous protons over a wide range of magnetic fields and of carbon-13 and protons of the sugar at high fields have been measured. The nuclear magnetic relaxation dispersion of water protons and the PREs of proton and carbon in the sugar are interpreted in terms of the model recently developed in our laboratory, allowing both outer- and inner-sphere PREs for water protons, but allowing only the outer sphere PRE for nuclei in the sugar. We found that the relative diffusion has a stronger effect on the PRE than the electron spin relaxation.</p>
166

Probing Dynamics of Oligosaccharides by Interference Phenomena in NMR Relaxation

Ghalebani, Leila January 2008 (has links)
Oligosaccharides (carbohydrates) are a large class of biological molecules that are important as energy sources in the human body and have enormously varied biological functions. It is generally believed that biological activities of carbohydrates are related to their internal dynamics. The dynamic properties of some oligosaccharides in solution are studied in this thesis, by NMR relaxation. We have employed relaxation interference effects to investigate the conformational dynamics within oligosaccharides (in-tramolecular dynamics) and paramagnetic relaxation enhancement (PRE) as an experimental tool to study intermolecular dynamics. Most of the thesis concerns the dynamics of the methylene group in the two possibly mobile parts of the oligosaccharide: in the exocyclic hydroxymethyl moiety and in the glycosidic linkage position. To perform conformational dynamic studies, the more traditional auto-relaxation pa-rameters are combined with the relaxation interference terms or the cross-correlated relaxation rates (CCRRs). Some experimental schemes based on the initial-rate technique were developed for measuring CCRRs. The techniques are useful for labelled sugars as well as naturally abundant ones. Furthermore, various dynamical models ranging from the Lipari–Szabo approach to several more informative and complicated models such as the two-site jump model, restricted internal rotation and slowly relaxing local structure (SRLS), have been employed to interpret our experimental data. We have combined and com-pared different models; we have also developed a novel approach to existing models, by scaling dipolar coupling constants (DCC), to extract the dynamic behaviour and structural properties of the system. We found that the auto- and cross-correlated relaxation data analyses yield a consistent picture of the dynam-ics in all cases. Additionally, our investigations show that CCRRs are practically important for verifica-tion of certain dynamical and structural information that is difficult to be determined by other means. Moreover, the anisotropy of the carbon-13 chemical shielding tensor in the methylene group has been estimated, using the interference between dipole-dipole and chemical shift anisotropy. This thesis also discusses using the PRE to investigate sugar dynamics relative to a paramagnetic MRI contrast agent in solution, which might be important in medicine. We have studied the intramolecu-lar dynamics of the trisaccharide raffinose in the presence of a gadolinium complex. We also investigated the effect of translational diffusion instead of rotational diffusion, which is normally more important in NMR. The paramagnetically enhanced spin–lattice relaxation rates of aqueous protons over a wide range of magnetic fields and of carbon-13 and protons of the sugar at high fields have been measured. The nuclear magnetic relaxation dispersion of water protons and the PREs of proton and carbon in the sugar are interpreted in terms of the model recently developed in our laboratory, allowing both outer- and inner-sphere PREs for water protons, but allowing only the outer sphere PRE for nuclei in the sugar. We found that the relative diffusion has a stronger effect on the PRE than the electron spin relaxation.
167

Nuclear Quadrupole Resonance And Relaxation Studies In Chloropyridines And High Pressure Studies In Chlorates

Amdjadi, Mohammed Hossein Ala 12 1900 (has links) (PDF)
No description available.
168

Nonradiative decay of singlet excitons in cadmium selenide nanoparticles

Anderson, Kevin David 23 September 2014 (has links)
Nonradiative decay of excitons is a competing process to Multi-Exciton Generation (MEG) in nanoparticles. Nonradiative decay of single excitons with sufficient energy to generate bi-excitons in Cd₂₀ Se₁₉ and Cd₈₃ Se₈₁ nanoparticles was studied using Tully's Molecular Dynamics with Quantum Transitions (MDQT) method and a CdSe pseudopo- tential. Exciton decay rates increase with increases in nanoparticle temperature and density of lower-lying excitonic states. There did not appear a significant effect of size on energy decay rates. The decay dynamics generally follow a gradual decay with transitions between nearby states. This is punctuated by periodic, short-lived periods of rapid downhill tran- sitions that result in a large proportion of excess exciton energy being transferred to the vibrational motion of the nanoparticle. The time for relaxation to below the 2.0E[subscript g] cutoff was on the order of 1ps. / text
169

Massage som omvårdnadsverktyg i intensivvårdsmiljö : En beskrivande studie

Johansson Hovstadius, Eva January 2005 (has links)
No description available.
170

EFFECTS OF A COMBINED RELAXATION AND MEDITATION TRAINING PROGRAM ON HYPERTENSIVE PATIENTS (BEHAVIORAL MEDICINE, COGNITIVE THERAPY, ANXIETY, STRESS, MULTI-PROCESS THEORY).

FRISKEY, LOUISE MAY. January 1984 (has links)
A growing literature suggests that training in relaxation or meditation results in significant reductions in blood pressure in hypertensive patients. The present study was designed to assess the efficacy of a combination relaxation and meditation training program structured by the author and previously used in treatment of a broad spectrum of anxiety-related clinical problems of either a medical (somatic) or a psychological (cognitive and emotional) nature. The 20 subjects were a heterogeneous clinical group of veterans with mild hypertension who were seen at the Tucson Veterans Administration Medical Center. Volunteers were randomly assigned to either (I) an education/cognition group, (II) a three-treatment relaxation/meditation group, or (III) a six-treatment relaxation/meditation group. Blood pressure, anxiety, and stress were measured at regular intervals during training and follow up. All groups were trained over a six-week period. Both relaxation/meditation groups were taught the same skills; only the schedules for training were varied. The educational group, conceived as a control for therapist attention, was, in fact, a cognitive treatment group. Statistically significant reductions in both systolic and diastolic blood pressure were found over time in all groups, while no difference in blood pressure reductions was found among the groups. Anxiety scores increased over time, and no correlation was found between subjective anxiety and objective blood pressure measures. Means of both systolic and diastolic blood pressure were lower at times when subjects reported no stress. Results of this study tend to support those of previous studies, finding statistically significant reductions in systolic and diastolic blood pressure over time in two groups of hypertensive subjects trained in relaxation and meditation techniques. No difference was found, moreover, between these groups and an education/cognition group, suggesting that group techniques, in either significant lowering of blood pressure. This finding lends support to a multiprocess theory which suggests that all treatments have multiple effects.

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